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+//===-- floatundixf.c - Implement __floatundixf ---------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements __floatundixf for the compiler_rt library.
+//
+//===----------------------------------------------------------------------===//
+
+#if !_ARCH_PPC
+
+#include "int_lib.h"
+
+// Returns: convert a to a long double, rounding toward even.
+
+// Assumption: long double is a IEEE 80 bit floating point type padded to 128 bits
+// du_int is a 64 bit integral type
+
+// gggg gggg gggg gggg gggg gggg gggg gggg | gggg gggg gggg gggg seee eeee eeee eeee |
+// 1mmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm | mmmm mmmm mmmm mmmm mmmm mmmm mmmm mmmm
+
+long double
+__floatundixf(du_int a)
+{
+ if (a == 0)
+ return 0.0;
+ const unsigned N = sizeof(du_int) * CHAR_BIT;
+ int clz = __builtin_clzll(a);
+ int e = (N - 1) - clz ; // exponent
+ long_double_bits fb;
+ fb.u.high.low = (e + 16383); // exponent
+ fb.u.low.all = a << clz; // mantissa
+ return fb.f;
+}
+
+#endif